In many fields of business activity, particularly in the field of logistics, so-called transponders are applied for the designation and later identification of goods and other items. These are communication devices which are capable of communicating with a communication apparatus. In this case, the communication is preferably wireless. With a frequently applied form of a transponder, the communication takes place by means of high frequency or radio signals. Such transponders are designated as high frequency transponders. If these are configured for identification purposes, they are described as so-called RFID-transponders (RFID →“Radio Frequency Identification”, high frequency identification).
An RFID-transponder normally comprises a transponder chip and an aerial. Electromagnetic signals are received by way of the aerial and are converted into electric signals which, by way of a connection between the aerial and the transponder chip, are then transmitted to the latter. The electric signals can then be evaluated in the transponder chip in order to receive information on an identification enquiry, for example. Following this, the transponder chip produces further electric signals as a response to the identification enquiry which are transmitted to the aerial and are converted by this into beam-capable electromagnetic signals.
The document DE 202 14 099 U1 discloses a beverage vessel, to which such a transponder is secured which has information electronically stored about the beverage vessel and its contents. Packing containers are described in the document DE 298 21 877 U1, where a transponder is secured by means of a special holder to each container. Holders are presented which ensure a reliable and extensively jolt-free holding of the transponder at the packing container.
Compared with a designation of items by way of non-electronic means, such as a barcode for example, RFID-transponders have the advantage that they can even then communicate by way of a high frequency connection by means of the communication apparatus if the RFID-transponder is arranged in the item or is otherwise covered off so that a visual identification is not possible. Furthermore, an information stored in the RFID-transponder can be changed or supplemented at all times.
If the item to be designated, however, comprises a metal component or is even completely formed from metal, there can be a detrimental effect on the function of the transponder because the metal component absorbs at least a part of the electromagnetic energy from the electromagnetic signals to be received or to be transmitted. If, for example, a transponder is arranged in an enclosed metal container, then the metal container forms a Faraday cage which substantially suppresses a communication between the transponder and an externally located apparatus.
In order to solve the problem of the negative effect on the function caused by the metal component, the attempt is made to secure the transponder or at least its aerial in such a way and as good as possible so that there is a maximum clearance between the metal component and the aerial. This is achieved, for example, by securing the transponder onto the surface of the metal component by means of a very thick adhesion film. However, the results of such an approach leave much to be desired, particularly in view of the fact that the attaching of a thick adhesion film leads to a situation where the transponder is standing away from the surface of the metal component.